--- /dev/null
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2010-2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#ifndef _LTTNG_UST_UTILS_H
+#define _LTTNG_UST_UTILS_H
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <urcu/compiler.h>
+
+/* For lttng_ust_is_integer_type */
+#if defined (__cplusplus)
+#include <type_traits>
+#endif
+
+
+/**
+ * lttng_ust_stringify - convert a literal value to a C string
+ */
+#define __lttng_ust_stringify1(x) #x
+#define lttng_ust_stringify(x) __lttng_ust_stringify1(x)
+
+/**
+ * lttng_ust_is_signed_type - check if type is signed
+ *
+ * Returns true if the type of @type is signed.
+ */
+#define lttng_ust_is_signed_type(type) ((type) -1 < (type) 1)
+
+
+/**
+ * lttng_ust_is_integer_type - check if type is an integer
+ *
+ * Returns true if the type of @type is an integer.
+ */
+#if defined(__cplusplus)
+#define lttng_ust_is_integer_type(type) (std::is_integral<type>::value)
+#else
+#define lttng_ust_is_integer_type(type) \
+ (__builtin_types_compatible_p(type, _Bool) || \
+ __builtin_types_compatible_p(type, char) || \
+ __builtin_types_compatible_p(type, unsigned char) || \
+ __builtin_types_compatible_p(type, short) || \
+ __builtin_types_compatible_p(type, unsigned short) || \
+ __builtin_types_compatible_p(type, int) || \
+ __builtin_types_compatible_p(type, unsigned int) || \
+ __builtin_types_compatible_p(type, long) || \
+ __builtin_types_compatible_p(type, unsigned long) || \
+ __builtin_types_compatible_p(type, long long) || \
+ __builtin_types_compatible_p(type, unsigned long long))
+#endif
+
+/**
+ * lttng_ust_ctf_array_element_type_is_supported -
+ *
+ * Adds a compilation assertion that CTF arrays and sequences declared by the
+ * user are of an integral type.
+ */
+#define lttng_ust_ctf_array_element_type_is_supported(type, item) \
+ lttng_static_assert(lttng_ust_is_integer_type(type), \
+ "Non-integer type `" #item "` not supported as element of CTF_ARRAY or CTF_SEQUENCE", \
+ Non_integer_type__##item##__not_supported_as_element_of_CTF_ARRAY_or_CTF_SEQUENCE);
+
+
+/**
+ * lttng_ust_runtime_bug_on - check condition at runtime
+ * @condition: the condition which should be false.
+ *
+ * If the condition is true, a BUG will be triggered at runtime.
+ */
+#define lttng_ust_runtime_bug_on(condition) \
+ do { \
+ if (caa_unlikely(condition)) { \
+ fprintf(stderr, \
+ "LTTng BUG in file %s, line %d.\n", \
+ __FILE__, __LINE__); \
+ exit(EXIT_FAILURE); \
+ } \
+ } while (0)
+
+
+/**
+ * lttng_ust_build_bug_on - check condition at build
+ * @condition: the condition which should be false.
+ *
+ * If the condition is true, the compiler will generate a build error.
+ */
+#define lttng_ust_build_bug_on(condition) \
+ ((void) sizeof(char[-!!(condition)]))
+
+
+/**
+ * lttng_ust_build_runtime_bug_on - check condition at build (if constant) or runtime
+ * @condition: the condition which should be false.
+ *
+ * If the condition is a constant and true, the compiler will generate a build
+ * error. If the condition is not constant, a BUG will be triggered at runtime
+ * if the condition is ever true. If the condition is constant and false, no
+ * code is emitted.
+ */
+#define lttng_ust_build_runtime_bug_on(condition) \
+ do { \
+ if (__builtin_constant_p(condition)) \
+ lttng_ust_build_bug_on(condition); \
+ else \
+ lttng_ust_runtime_bug_on(condition); \
+ } while (0)
+
+
+/**
+ * lttng_ust_offset_align - Calculate the offset needed to align an object on
+ * its natural alignment towards higher addresses.
+ * @align_drift: object offset from an "alignment"-aligned address.
+ * @alignment: natural object alignment. Must be non-zero, power of 2.
+ *
+ * Returns the offset that must be added to align towards higher
+ * addresses.
+ */
+#define lttng_ust_offset_align(align_drift, alignment) \
+ ({ \
+ lttng_ust_build_runtime_bug_on((alignment) == 0 \
+ || ((alignment) & ((alignment) - 1))); \
+ (((alignment) - (align_drift)) & ((alignment) - 1)); \
+ })
+
+
+/**
+ * lttng_ust_offset_align_floor - Calculate the offset needed to align an
+ * object on its natural alignment towards lower addresses.
+ * @align_drift: object offset from an "alignment"-aligned address.
+ * @alignment: natural object alignment. Must be non-zero, power of 2.
+ *
+ * Returns the offset that must be substracted to align towards lower addresses.
+ */
+#define lttng_ust_offset_align_floor(align_drift, alignment) \
+ ({ \
+ lttng_ust_build_runtime_bug_on((alignment) == 0 \
+ || ((alignment) & ((alignment) - 1))); \
+ (((align_drift) - (alignment)) & ((alignment) - 1)); \
+ })
+
+#endif /* _LTTNG_UST_UTILS_H */
projects / lttng-ust.git / blobdiff